Flowchart Maker and Online Diagram Software

diagrams.net (formerly draw.io) is free online diagram software. You can use it as a flowchart maker, network diagram software, to create UML online, as an ER diagram tool,
to design database schema, to build BPMN online, as a circuit diagram maker, and more. draw.io can import .vsdx, Gliffy™ and Lucidchart™ files .